To establish the relationship between EEG sleep, sympathetic tone and immune function, to characterize the nocturnal profile of lymphokines, neuroendocrine hormones and sympathetic neurotransmitters in sleep activity, to examine the association between nocturnal secretions of lymphokines, hormones and catecholamines and alterations of immune function in psychiatric patients and to test link between sleep, neuroendocrine and sympathetic measure and immunologic responses using partial sleep deprivation.